WatchdogTimer

Index: 0083 (83)
Size: 3936 bytes (PE32+ body)
Phase: DXE (Driver eXecution Environment)
Subsystem: EFI_BOOT_SERVICE_DRIVER (0x0B)

Overview

Watchdog Timer UEFI Driver. Implements the EFI_WATCHDOG_TIMER_ARCH_PROTOCOL for the HR650X platform. The watchdog timer is a hardware feature that resets the system if firmware or software becomes unresponsive within a configurable time period. Provides RegisterHandler, SetTimerPeriod, and GetTimerPeriod services. On timer expiry, calls the registered notification handler then resets the system via gRT->ResetSystem(). Coordinates with the SMM watchdog handler via the SMM Communication Protocol to synchronize watchdog state between DXE and SMM phases.

Key Functions

• WatchdogTimerDriverEntry -- Module entry point; installs the Watchdog Timer Architectural Protocol
• WatchdogTimerRegisterHandler -- Registers a notification handler to be called on watchdog expiry
• WatchdogTimerSetTimerPeriod -- Sets the watchdog timer period and enables/disables the watchdog
• WatchdogTimerGetTimerPeriod -- Returns the current watchdog timer period
• WatchdogTimerHandler -- Internal handler invoked on timer expiry; calls registered notification then resets system
• WatchdogSmmSync -- Synchronizes watchdog state with the SMM watchdog handler

Protocols / Dependencies

• EFI_WATCHDOG_TIMER_ARCH_PROTOCOL (gEfiWatchdogTimerArchProtocolGuid) -- {665E3FF5-46CC-11D4-9A38-0090273FC14D}
• EFI_SMM_COMMUNICATION_PROTOCOL -- Communication with SMM watchdog handler
• EFI_RUNTIME_SERVICES -- ResetSystem() for system reset on watchdog expiry
• UEFI Boot Services -- Protocol installation and timer management
• HOB List -- Access to HOB data for debug output device detection

Platform

HR650X BIOS, x86-64 architecture. Module originates from MdeModulePkg/Universal/WatchdogTimerDxe (EDK2).